If you have a niche but cannot vocalise it, then you will not be able to communicate it in a compelling way and so it's not really a niche.
Your target market or person needs to be understood by you, in order for you to be able to motivate or influence them. Different groups of people have different values or want different outcomes and by narrowing your search you will be able to find them easily and let them know what you offer that they need or desire.
This is the area that is most difficult to get to grips with but the whole exercise can be repeated for other niches you may have. I have 3 niches - schools, small business owners and teams but the language I use while in a classroom of teachers and their pupils, is nothing like my elevator pitch that I would use in a business setting. Obvious, yes, but missed by so many organisations. Work out who your decision maker or buyer is within your niche.
Another way to differentiate yourself is by the 4th P, which is Process. So if you are in a niche where there are other companies that do the same thing as you with a similar group of people, then you can stand out by making the process in which you deliver this service, unique. One great example of this is the new craze for getting rid of dead skin on your feet by sticking them in water and allowing small fish to nibble away. Beauty salons all over the uk are able to give the same result but the fish thing is a compelling and fun way of achieving smooth feet!
So try and communicate your niche using pain, person, process in a passionate 30 second elevator pitch and try it out next time you are networking.